Fuel-air mixture setting on carby

[dave]

Hi again,

OK this is going to appear really dumb to some people, but I'm about as mechanically minded as Princess Mary of Denmark, so it's a legitimate question for me.

I need to tune up my ratBellett 1600 (Florian motor, but I think it's safe to assume it's tuned about the same as a Bellett 1500) and I was wondering if there is a set amount of turns that the fuel-air mixture screw thingo should be set at.

I would assume it probably depends on the condition of the motor and carby, but this thing is pretty tight so whatever is the stock setting (if there is such a thing) would probably be the go.

If my question is stupid, Jedi masters pls forgive!


Cheers,


Dave

[PR91]

i know that weber/delloro/solex's are set at 1.5 turns OUT from fully in, and holley's are the same.
maybe that would be a starting point??

i've found that it's a case of starting at this "1.5 turns out" point, and turning the screw outwards half a turn at a time, counting the half turns as you go, until it runs rough, then wind the screw back in half a turn. some guys with race car i know wind the screw in a full turn, as the richer mixture suits them better at higher revs.
winding the screw outwards leans the mixture out, winding it in richens it.
if you find it runs better and better by winding the screw inwards, and it doesn't stall before being wound all the way in (ie: full rich), then the jets are too small.

this system seems to work fine on my cars (obviously the GT is excluded, as it's got hitachi/su's, and they are a totally different idea). i know that the wasp is set at about 2.5 turns out.

[IZU069]

1.25 turns.

[Beetle]

Dave just remember the only stupid question is the one you didn't ask.
If we all ask questions we will all learn something!
Cheers Beetle

[Stickman]

Amen to that Beetle!
I've lived by that theory all my life.
I've learnt one or two things along the way too dispite some of the sniggers from behind.

The thing is, Dave HAS the answer!

Stickman